//author by wangjun  edit 2010-12-4
jQuery.cookie = function(name, value, options) {
    if (typeof value != 'undefined') { // name and value given, set cookie
         options = options || {};
        if (value === null) {
             value = '';
             options.expires = -1;
         }
        var expires = '';
        if (options.expires && (typeof options.expires == 'number' || options.expires.toUTCString)) {
            var date;
            if (typeof options.expires == 'number') {
                 date = new Date();
                 date.setTime(date.getTime() + (options.expires * 24 * 60 * 60 * 1000));
             } else {
                 date = options.expires;
             }
             expires = '; expires=' + date.toUTCString(); // use expires attribute, max-age is not supported by IE
         }
        var path = options.path ? '; path=' + options.path : '';
        var domain = options.domain ? '; domain=' + options.domain : '';
        var secure = options.secure ? '; secure' : '';
         document.cookie = [name, '=', encodeURIComponent(value), expires, path, domain, secure].join('');
     } else { // only name given, get cookie
        var cookieValue = null;
        if (document.cookie && document.cookie != '') {
            var cookies = document.cookie.split(';');
            for (var i = 0; i < cookies.length; i++) {
                var cookie = jQuery.trim(cookies[i]);
                // Does this cookie string begin with the name we want?
                if (cookie.substring(0, name.length + 1) == (name + '=')) {
                     cookieValue = decodeURIComponent(cookie.substring(name.length + 1));
                    break;
                 }
             }
         }
        return cookieValue;
     }
};